[CodeGen] Print "%vreg0" as "%0" in both MIR and debug output

As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).

Basically:

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed

Differential Revision: https://reviews.llvm.org/D40420

llvm-svn: 319427
diff --git a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
index 2c52e16..5215740 100644
--- a/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp
@@ -290,11 +290,11 @@
     // copy since a subregister use tied to a full register def doesn't really
     // make sense. e.g. don't fold:
     //
-    // %vreg1 = COPY %vreg0:sub1
-    // %vreg2<tied3> = V_MAC_{F16, F32} %vreg3, %vreg4, %vreg1<tied0>
+    // %1 = COPY %0:sub1
+    // %2<tied3> = V_MAC_{F16, F32} %3, %4, %1<tied0>
     //
     //  into
-    // %vreg2<tied3> = V_MAC_{F16, F32} %vreg3, %vreg4, %vreg0:sub1<tied0>
+    // %2<tied3> = V_MAC_{F16, F32} %3, %4, %0:sub1<tied0>
     if (UseOp.isTied() && OpToFold.getSubReg() != AMDGPU::NoSubRegister)
       return;
   }
@@ -971,7 +971,7 @@
       // Prevent folding operands backwards in the function. For example,
       // the COPY opcode must not be replaced by 1 in this example:
       //
-      //    %vreg3<def> = COPY %vgpr0; VGPR_32:%vreg3
+      //    %3<def> = COPY %vgpr0; VGPR_32:%3
       //    ...
       //    %vgpr0<def> = V_MOV_B32_e32 1, %exec<imp-use>
       MachineOperand &Dst = MI.getOperand(0);